1. Field of the Invention
The instant invention relates to walking canes having auxiliary handles to assist a seated person to rise to a standing position.
2. State of the Art
Various types of devices have been utilized to assist people recovering from various types of injuries and surgery or experiencing weakness or instability from conditions associated with advanced age or other causes to help such a person move from a seated position to a standing position.
Complicated devices such as tilting chairs and the like have been utilized. Also, various types of four legged walkers and devices designed to be supported by a chair or bed have been utilized for this purpose.
Although the problem has existed from time immemorial, it still receives considerable attention from the medical community and numerous articles have been recently written. Exemplary articles of this type include the following:
"Rising from a Chair: Effects of Age and Functional Ability on Performance Biomechanics," Journal of Gerontology: Medical Sciences, v. 46, n. 3 (1991), M91-98 by Alexander, Schultz and Warwick. PA1 "Walking Stick Used by the Elderly," British Medical Journal, v. 284, p. 1751, 12 Jun. 1992, Sainsbury & Meilley. PA1 "Every day Aids a Appliances--Walking Sticks," British Medical Journal, v. 296, 13 Feb. 1988, Mulley. PA1 "The Influence of Chair Height on Lower Limb Mechanics During Rising," Journal of Orthopaedic Research (1989), 7:266-271.
"Design and Use of Improved Walking Aids," J. Biomed Eng., v. 7, Oct. 1985, Nava and Laura.
These articles discuss several matters including the desirability of arm rests on chairs in assisting uprisal in preference to greater chair height, the desirability of correctly sizing the height of a walking stick and the necessity of walking sticks for a significant portion of the population over age 75. Also, a retractable crutch which can have its shoulder support lowered to assist a person during seating from a standing position is discussed. This crutch, discussed in the last cited article, has a spring which compresses to provide a "stored" force to raise the shoulder piece to a fully extended height upon spring release prior to uprisal.
Developers in the field have given attention to the problem and various cane or cane-like devices are disclosed in a number of patent or patent-related documents. British patent application No. GB2136290A of Walker, U.S. Pat. No. 3,289,685 of Parker, and U.S. Pat. No. 4,562,850 to Early et al. disclosed devices with a plurality of handles and a cane-like structure. Also, the patent to Warry, U.S. Pat. No. 1,400,394 discloses a telescoping crutch-like device with a single shaft wherein an auxiliary handle may be gripped when the crutch is fully extended so that its top support fits under the arm of an individual.
The device of Walker has four handles at the top of the device wherein the lower handles may be gripped by a person seated for the purpose of pulling on the handles with the device in a frontal position to attempt to pull oneself into a standing condition. The upper and lower handles of the Walker device are located close to one another and the device is such that it has two pair of handles located at two different levels of the cane. The device of Parker has two handles, but the handles are not located with their geometric centers above the shaft member. The principal use of the two handles of the Parker cane is for stability when a user is traversing uneven terrain, although the patent mentions its use for uprisal purposes. The upper and lower handles of Parker are relatively close together, e.g., about six inches. Thus, as one attempts to use these canes, the pressure of the handles will cause some rotational force upon the wrist of the user when trying to rise from a seated position and since many users have arthritic conditions, torque on the wrist is generally to be avoided. Furthermore, the handles of the Parker device are sufficiently so close together that one utilizing such a cane, especially alongside a chair, would experience an uncomfortable position for the wrist, hand, and forearm because of the limited space available between the handles. Again, as with the Walker device, the more comfortable and biomechanically advantageous position to which to use a cane for uprisal purposes, is alongside a chair and close to one's center of gravity when seated. The close proximity of the two handles of Parker does not really permit this type of convenient use of the device so one can push down upon a lower handle rather than trying to pull oneself into an erect position.
The device of Early has a collar close to the handle of the cane wherein the collar provides a small surface for a person to try to pull on to pull oneself into a standing position. The collar is too close to the handle to be used in a pushing-down motion and again it appears that this is a cane structured toward use in front of a seated user.
Another patent having a supplementary handle is U.S. Pat. No. 4,121,605 to Schmerl which has a rather long stabilizing bar which is pivoted in close proximity to the cane handle wherein the bar may be rotated to a substantially perpendicular position with respect to the cane shaft wherein a second hand may be comfortably placed along the stabilizing bar when a user of the cane has his or her other hand on the cane handle and is apparently in a standing position. This bar is also located close to the main cane handle so that it would not be useful in assisting a person rising from a chair unless that user was trying to pull on the stabilizing bar.
Other structures, such as that illustrated in U.S. Pat. No. 4,941,495 of Boyce et al. have also been utilized to provide uprisal aid. This device has a pair of "arm rests," which are laterally spaced a sufficient distance to encompass the hips of a user. These "arm rests" provide hand support for a person rising from a seated to a standing position.